Re: Solution for including a file only once

[Reinhold Kainhofer]

Am Donnerstag, 11. Februar 2010 18:18:52 schrieb Michael J. O'Donnell:
> For the very short term, I expect that "\includeIfAbsent", or whatever
> we call it, will be most useful if it duplicates the current behavior of
> "\include" as much as possible, except when it does nothing due to a
> previous inclusion. So, I'm going to stack thoughts about specific uses
> and connections to name spaces. 

In my view there are two different kinds of include uses:
1) To include package-like .ily files, which define additional functionality. 
There many utility functions really might/should be in their own namespace, 
but many definitions (and in particular all \header, \paper or \layout blocks) 
need to be at toplevel.

2) Included music definitions, where you define parts (or smaller building 
blocks, which are used all over the place) of your scores. These definitely 
should simply be inserted into the stream without namespaces and the like.

> I will try to insert them into the GLISS
> discussion---I don't know Hans' programming ideology, but I think that
> systems like LilyPond should follow best programming language practice
> as much as possible. 

I think it should be as easy and straightforward to use to a non-programmer as 
possible, while allowing more complex use without making easy things harder 
than necessary for easy things. 

Cheers,
Reinhold
-- 
------------------------------------------------------------------
Reinhold Kainhofer, address@hidden, http://reinhold.kainhofer.com/
 * Financial & Actuarial Math., Vienna Univ. of Technology, Austria
 * http://www.fam.tuwien.ac.at/, DVR: 0005886
 * LilyPond, Music typesetting, http://www.lilypond.org